Introduction of a drag reducing substance near the affected surface of a moving object is known in the art. For example, injection of a fluid into the boundary layer of a fluid flow is known to substantially reduce skin friction drag for vehicles moving relative to the flow. The benefits of drag reduction are clear, including enhanced speed and acceleration, as well as fuel savings. In the case of surfing, reduced drag may translate into a substantially improved ability to propel a surfboard and catch a wave, as well as a longer and faster ride. In cases of water skiing and similar activities, reduced drag may mean greater maneuverability, less resistance to the pulling boat, higher top speeds and less stress on the skier's legs. In sum, the potential advantages of drag reduction abound for recreational vehicles. Yet, despite these benefits, heretofore, fluid injection systems have not been adapted specifically for such recreational use.
While fluid injection systems have, been applied to large naval vessels, such as ships and submarines, as well as aircraft, such systems tend to be bulky, complex, costly and generally unsuitable for use with recreational vehicles. For example, some prior systems employ sophisticated processing systems to monitor fluid flow in or near the boundary layer and to control injection characteristics with precision. Some also require large power supplies and a complex network of tanks, pumps, controllers, independently controlled valves and individual nozzles to consistently achieve desired injection characteristics.
In general, prior systems are not tailored to provide a burst of injection for a relatively brief period of time. Rather, they contemplate substantially constant fluid injection for a relatively long duration. Consequently, such systems depend upon either large storage facilities to supply the fluid for injection or a system for harnessing ambient fluid as a supply source. The former typically requires massive storage tanks, and the latter typically requires bulky and expensive pumps or compressors.
Prior systems also do not address a means for user activation. In sharp contrast, they tend to be complex automated systems, taking the individual pilot or captain out of the loop. A recreational user may prefer to control the speed and acceleration benefits attributed to fluid injection.
Thus, a fluid injection drag reduction system that is light-weight, compact, easy to use and maintain, affordable and controllable by the user is needed for recreational vehicles.